The use of metal oxide-coated platelets to form a basis of a pigment providing one or more of various visual effects, including a pearlescent lustre and a metallic lustre, has been disclosed in, for instance, Pigment Handbook, Vol. 1, Second Edition, pp 829-858 (John Wiley & Sons, N.Y. 1988).
U.S. Pat. No. 5,753,371 discloses a pearlescent pigment consisting essentially of flakes of C glass having a layer comprising iron oxide or rutile titanium dioxide thereon. The source for the rutile titanium dioxide is stated to be selected from titanium tetrachloride and titanyl sulphate.
While the glass baked pigment of U.S. Pat. No. 5,753,371 can be provided in a form which is a high quality, high lustre pearlescent pigment, it is relatively expensive to produce and there is a need for an alternative, preferably cheaper to produce, material which is of high quality.